It's been a rollercoaster morning for London's blue chips, although pretty much all the volatility has happened in negative territory as miners struggle.HSBC, little changed at lunchtime, has hogged the headlines. Reports suggest that current chief executive Mike Geohegan will leave at the end of the year after missing out on the executive chairman job.There's also talk the banking giant is threatening to move its headquarters out of the UK if thinks recommendations from the government-appointed Independent Commission on Banking are too draconian.The ICB today confirmed it will consider whether the major UK banks should split their retail and investment arms or be forced to divest assets to boost competition. Among the movers, miners are worst of the bunch, headed by Kazakhmys, Antofagasta and Anglo-American after a downbeat note from UBS.The Swiss broker cut Antofagasta to 'sell' from 'neutral', while drops to 'sell' from 'buy'. "We believe the time is right for investors to take profits following the recent outperformance of both stocks and our cautious near-term view on copper [prices]," UBS said in a note to clients. Both Anglo and Vedanta drop to 'neutral' from 'buy'.Elsewhere, BHP Billiton has received the green light for development of the Macedon gas field in the Exmouth Sub-basin, Western Australia. Project costs will be in the region of $1.5bn. BHP's rival, Rio Tinto, meanwhile, is to plough $230m into its operations at the Dampier Port in Western Australia to expand capacity. Dana Petroleum's valiant rearguard action against the takeover bid by the Korea National Oil Corporation (KNOC) has failed. KNOC has declared its £18 a share offer wholly unconditional after almost two-thirds of Dana's shareholders backed the deal. The Koreans went hostile a month ago after Aberdeen-based Dana refused their advances, declaring the company worth far more than the £1.8bn on the table. Also on the bid front, Intec is recommending a bid from American firm CSG worth 72p a share in cash, £237m, that the struggling telco billing systems firm believes has a "sound strategic rationale". Business publisher Euromoney is predicting record full-year profits following a recovery in sales during August and September. Wireless products specialist Filtronic's trading in the first quarter has picked up from the weak final quarter of last year, though conditions remain difficult overall. Sales are running at around £1m per month.